Thanks for the answers guys. I have (2) D-120's supplemented with 48 Cree LED over 120gallon. The Cree's alone have a 300 PAR. I only have the whites at 45% but i do have the blues at 85-90% I had to lower the blues at about 60% to get the PAR at 600 range. I will play a bit more tonight and try to get it down and to my liking. I also have 8 greens, 4 cyan and 4 Reds over the tank.